# demo02_elif.py
score = int(input("score: "))
if score < 0 or score > 100:
    print("成绩不合法!!!")
elif score >= 90:
    print("you xiu")
elif score >= 80:
    print("hao")
elif score >= 70:
    print("liang")
elif score >= 60:
    print("ji ge")
else:
    print("你要努力了~")